► New Mercedes G-class imminent ► Set to be lighter and more spacious► Expected to feature E-class tech

It’s been some 38 years since the first Mercedes-Benz Geländewagen clambered over a rocky crest and onto the scene. Despite being developed as a military vehicle, and having a distinctly utilitarian design, it found success in the wider public market. Thanks to continued demand and some significant revisions along the way, the Mercedes-Benz G-class is still going strong.

So much so, in fact, that Mercedes is about to relaunch the classic off-roader to keep it going for another decade. Our spies have captured the new 2018 G-class on test in Germany - we've got photos of it alongside the current car (last updated with a host of cosmetic and powertrain upgrades in late 2015), splattered in mud after off-roading trials and fresh pictures of the red-hot new AMG version.

The G-class – in its current W463 generation – has been around since 1990, at which point the G-wagen name was dropped. Time, then, for a major refresh...

Oh look, it’s been completely restyled. Not!

Admittedly, the looks will not change dramatically – after all, how do you restyle something that’s based on two boxes stuck together? – but these spy shots do reveal that the new G-class will be slightly wider. Our sources suggest the girth will swell from 1760mm to 1860mm.

While that’ll make it even trickier to manage on tighter roads, those inside will likely appreciate the extra space. It’s also expected to be far lighter than the current G-class, which clocks in at a mighty 2612kg in G 350d form.

Previous spy shots featured what was believed to be a conventional diesel G-class, but it’s understood that this more aggressively styled prototype (above) is a G63 AMG.

The huge brake discs and red calipers are one telltale sign, as is the outrageous side-exit exhaust. There's plenty of additional cooling and plumbing for the anticipated V8 engine.

If it does indeed share its engine with Mercedes-AMG’s other 63 offerings, then expect a power output in the region of 600bhp. You can already get a G500 with a 416bhp version of the 4.0-litre twin-turbo V8 in some markets, so it seems a straightforward move.

There are expected to be more significant changes inside, however, with the rumoured adoption of Mercedes’ latest interior tech from the E-class. Time will tell as to whether it’ll receive the digital instrument panel – but you can rest assured that the original designers never envisioned the G-class featuring such advanced technology...

Any new engines in the works for the 2018 Mercedes-Benz G-class?

As well as the aforementioned 4.0-litre twin-turbo V8 that’s used in the Mercedes-AMG C63, you can expect more conventional petrol and diesel offerings, too, for those who want to trade straight-line speed for range.

And the G is likely to adopt hybrids and electrification in the course of its lifetime.

Production of the new G-class will take place in the Magna Steyr plant in Graz, Austria, where the current version is built. We’re also told that the new model may run alongside the old version for a time, with the outgoing G-class existing as the ‘basic’ variant in the range for a time.

When’s the new G-class due?

There’s no official word on when the new model might arrive but, we’re expecting to see the new 2018 G-class in the next few months ahead of a spring '18 showroom launch.

Word is, this relaunch will keep the G-wagen type approved until 2027. It's the car that just can't be killed...